• The latest ranking highlights the continued success Chinese apps are having in the U.S., with Bytdance's TikTok ranking third and Temu-competitor Shein coming in at number 12.
• Temu's success comes amid increased scrutiny by U.S. officials, which might worsen under the incoming Trump administration.

Temu, the popular e-commerce app owned by China's PDD Holdings, topped Apple's list of the most downloaded free apps on its U.S. iOS store for the second year running, highlighting the massive success that Chinese apps are enjoying in the world's largest consumer market.

ByteDance's TikTok came in third in the ranking despite doubts over its ability to continue operating in the U.S., while Temu-competitor and fast-fashion giant Shein came in at number 12.

Apple's iOS accounts for over 56% of U.S. mobile phone market, according to data from StatCounter.

Temu, which ships cheap goods from China, first entered the U.S. market in 2022. It has taken the market by storm, putting pressure on incumbent heavyweight Amazon.

The Chinese company, however, faces increased scrutiny from U.S. officials, and risks posed by tariffs which the incoming Trump administration has promised to raise.

Regulatory scrutiny, tariffs risks

As the likes of Temu and Shein attract American consumers with cheap goods and aggressive advertising, they have also caught the attention of Washington. 

In September, the Biden administration announced a new proposal aimed at blocking the "overuse and abuse" of the long-standing "de minimis" provision by companies such as Shein and Temu. The provision allows shipments valued under $800 certain import duty exemptions. 

If Temu and Shein were to lose their de minimis exemption, it could push up prices and reduce the Chinese companies' competitiveness, experts have told CNBC.

Donald Trump's impending return to the White House adds another layer of uncertainty as the president-elect made curbing imports from China a major focus of his campaign. Trump has proposed tariffs as high as 60% to 100% on goods from China, although it is unclear whether he will carry out his threat.

U.S. officials are not the only ones concerned about Chinese imports flooding their domestic markets.

In Southeast Asia, Vietnam and Indonesia have imposed a range of anti-dumping tariffs on Chinese goods, while Thailand recently announced measures to monitor cheap imports. Earlier this month, Vietnam banned Temu from operating in the country just two months after the Chinese company set up a local presence.

In a global outlook report released Friday, Nomura said that its U.S. economics team expects changes to the de minimis rule to be a key trade priority for the Trump administration, perhaps second only to hiking tariffs. 

"This represents another major downside risk to China's exports to the U.S. in 2025," the report said.

Nomura estimates a U.S. ban on all de minimis imports from China could reduce the latter's annual export growth by 1.3% and drag GDP growth down by 0.2%.